The way TeamViewer, LogMein and GoToMyPc work is the company that provides the software does the referring so you just tell the client to download a small file and execute it.
For some reason TeamViewer under Wine doesn't want to work. TeamViewer under Ubuntu works fine, but Sam (my friend) is really liking PC-BSD and wants to switch.
SSH would work if he could go to the customer's house and set it up first, but the service call is usually started from a phone call rather than a site visit.
@Cobalt: Whatever your brothers are using, please hook me up.
Thanks everyone, appreciate it.